Field of the Invention
The present disclosure relates generally wound dressings, and in particular to a delivery apparatus for the application of thin film dressings over a wound for use in a treatment such as negative wound pressure therapy.
Description of the Related Art
Wound dressings are generally placed over a wound to protect and promote healing of the wound. One type of wound dressing consists essentially of a thin membrane of a polymer or similar material, coated on an underside with a pressure-sensitive adhesive. The adhesive may adhere the dressing to healthy skin surrounding the wound such that the dressing provides an effective bacterial barrier to protect the wound from contamination. Because of their extremely elastic nature, thin polymeric film dressings may readily conform to irregular contours of a patient's skin while promoting patient movement and comfort. This type of dressing may also be sufficiently transparent to pelmit visual inspection of the wound without the need for removing the dressing and exposing the wound to contaminants in the environment.
One technique that may utilize a thin film dressing may be described as negative wound pressure therapy (NWPT). The thin film dressing may be positioned to form a substantially fluid tight seal with the skin surrounding the wound to define a reservoir over the wound where a negative pressure may be maintained. The reservoir subjects the wound to a sub-atmospheric pressure to effectively draw wound fluid, including liquid exudates, from the wound with, e.g., a vacuum pump. Vacuum pressure may be applied continuously, or in varying intervals, depending on the nature and severity of the wound. This technique has been found to promote blood flow to the wound area, stimulate the formation of granulation tissue and encourage the migration of healthy tissue over the wound. This type of treatment may subject a thin film dressing to repeated changes of size and shape, taking advantage of the flexibility of the dressing.
The flexibility of a thin film dressing may, however, present difficulties in the application of the dressing to a wound site. For example, the dressing may tend to fold, wrinkle and adhere to itself. To mitigate these tendencies, a delivery layer may be supplied with the dressing to temporarily support the dressing until the dressing is applied. When a thin film dressing is applied as part of an NWPT treatment, additional concerns arise including properly sizing the dressing and appropriately locating a vacuum port relative to the wound. Accordingly, a need exists for a composite dressing and delivery apparatus suitable for use in conjunction with an NWPT treatment.